Water cluster

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Water clusters are unstable, mostly short-lived associations of water molecules to form larger molecular assemblies.

Use of the term in physical chemistry

Concatenation of the water molecules via hydrogen bonds to form clusters

The assumption that these objects exist is based on the well-known anomaly of water . For its molecular mass, water has an unusually high melting and boiling point, which is explained by the very strong hydrogen bonds compared to other intermolecular forces . They connect the water molecules, which leads to properties that usually only have much heavier substances.

According to structural studies by the University of California in 2006, long chains and rings form briefly in liquid water, within which the water molecules are tetrahedrally surrounded by four other water particles, like in solid ice .

The density anomaly , namely that water decreases its density when it cools down from 3.98 ° C to freezing point, is also explained by the onset of the formation of crystal-like structures. However, the structures mentioned are unstable and by no means firmly bonded molecular assemblies.

There is a constant fluctuation in the water molecules that are bound to one another by hydrogen bonds. Hydrogen bonds only exist for a very short time and break up again within picoseconds , while new bridges and thus new clusters form just as quickly at other binding sites.

The lifetime of a hydrogen bond is typically in the range of 1 ... 20 ps (ps = picosecond = 10 −12 seconds), which makes experimental research into water clusters difficult. Experimentally, the extreme transience of the microstructures is also at the water rotational diffusion of the water to realize this is the random by random movements generated change the direction of the axes of symmetry of the water molecules in the liquid whose characteristic times also lying in the picosecond range.

These special properties of water are the reason for its numerous anomalies.

A permanent restructuring of the clusters ( up to the customer ), called " (positive) informedness " in esoteric language , is impossible because of the short life of each individual hydrogen bond.

Use of the term in esotericism

The short-lived water clusters are referred to in esotericism and in water revitalization systems (see revitalized water ) as transient carriers of unspecified information . The best-known representative of these fantasies is the Japanese para-scientist Masaru Emoto . He claims that water stores emotions and that this can be recognized by the structures of snow and ice crystals . Water clusters are also said to be responsible for the alleged transmission of information in water in homeopathy . The alleged pseudoscientific effects have not been systematically proven, nor are they based on scientific knowledge.

Individual evidence

  1. ↑ Detected water dimers in the atmosphere for the first time. In: Ruperto Carola. Edition 03/2003.
  2. ↑ A. Geiger, I. Brovchenko, D. Paschek, Ralf Ludwig: Molecular properties and function of water , molecular clusters and liquids (PDF; 757 kB), UNIREPORT special edition Chemiedozententagung 2004, University of Dortmund.
  3. ↑ Lynn Yarris: Curtain May be Closing on Scientific Water Controversy , ResearchNews des Berkley Lab, June 26, 2006.
  4. ↑ Teresa Head-Gordon, Margaret E. Johnson: Tetrahedral structure or chains for liquid water
  5. ↑ Frank N. Keutsch and Richard Saykally : Water clusters: Untangling the mysteries of the liquid, one molecule at a time In: Proceedings of the National Academy of Sciences USA . 2001: 98: 10533-10540. doi : 10.1073 / pnas.191266498 (English)
  6. ↑ FN Keutsch, RJ Saykally : Water clusters: Untangling the mysteries of the liquid, one molecule at a time. In: Proceedings of the National Academy of Sciences USA. 98, 2001, pp. 10533-10540, doi : 10.1073 / pnas.191266498 .
  7. ^ Felix Franks: Water a matrix of life. 2nd edition, RSC Paperbacks, Cambridge 2000, p. 28. ISBN 0-85404-583-X . (English)
  8. ^ Y. Thomas: The history of the memory of water . In: Homeopathy . tape 96 , no. 3 , 2007, p. 151-157 , PMID 17678810 .
  9. ↑ J. Teixeira: Can water possibly have a memory? A skeptical view . In: Homeopathy . tape 96 , no. 3 , 2007, p. 158-163 , PMID 17678811 . (online at: badscience.net )

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